thanks, do you have an
example of this ?
Federica
Earwin Burrfoot ha scritto:
Isn't it better to have specially prepared sort fields? Like
lowercased, if you want case-insensitive comparisons, or stripped of
whitespace and punctuation, like I did once.
That way you have more flexibility and also don't kill performance outright.
On Fri, May 8, 2009 at 11:58, Federica Falini Data Management S.p.A
<[email protected]> wrote:
Hi,
in Lucene 2.4.1 (as such in Lucene 2.2) the term enumeration is sorted
case-sensitive: first capital and then small;
For example, this sort on TermEnum is wrong for human consumption:
Annales
Cafè
Zucche
cafe
this is the correct sort in this case :
Annales
cafe
Cafè
Zucche
In Lucene 2.2 i have made modification on Term.java, TermBuffer.java
(see below) in order to have Term enumerations sorted case-insensitive:
TermEnum terms = reader.terms(new Term("myFieldNotTokenized", ""));
while ("myFieldNotTokenized".equals(terms.term().field())) {
System.out.println( " " + terms.term());
if (!terms.next()) break;
}
Now in Lucene 2.4 i find it difficult because the package "index" is
changed a lot; can i have some indications to keep my sort?
Thanks in advance
Federica
Here below the modified class on Lucene 2.2
Term.java:
package org.apache.lucene.index;
import java.text.CollationKey;
/**
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
A Term represents a word from text. This is the unit of search. It is
composed of two elements, the text of the word, as a string, and the name
of
the field that the text occured in, an interned string.
Note that terms may represent more than words from text fields, but also
things like dates, email addresses, urls, etc. */
public final class Term implements Comparable, java.io.Serializable {
String field;
String text;
transient CollationKey ckText;
/** Constructs a Term with the given field and text.
* <p>Note that a null field or null text value results in undefined
* behavior for most Lucene APIs that accept a Term parameter. */
public Term(String fld, String txt) {
this(fld, txt, true);
}
Term(String fld, String txt, boolean intern) {
field = intern ? fld.intern() : fld; // field names are interned
text = txt; // unless already known to be
ckText = OpacCollator.getInstancePool().getCollationKey(text);
}
/** Returns the field of this term, an interned string. The field
indicates
the part of a document which this term came from. */
public final String field() { return field; }
/** Returns the text of this term. In the case of words, this is simply
the
text of the word. In the case of dates and other types, this is an
encoding of the object as a string. */
public final String text() { return text; }
/**
* Optimized construction of new Terms by reusing same field as this Term
* - avoids field.intern() overhead
* @param text The text of the new term (field is implicitly same as this
Term instance)
* @return A new Term
*/
public Term createTerm(String text)
{
return new Term(field,text,false);
}
/** Compares two terms, returning true iff they have the same
field and text. */
public final boolean equals(Object o) {
if (o == this)
return true;
if (o == null)
return false;
if (!(o instanceof Term))
return false;
Term other = (Term)o;
//return field == other.field && text.equals(other.text);
return field == other.field && text.equalsIgnoreCase(other.text);
}
/** Combines the hashCode() of the field and the text. */
public final int hashCode() {
return field.hashCode() + text.hashCode();
}
public int compareTo(Object other) {
return compareTo((Term)other);
}
/** Compares two terms, returning a negative integer if this
term belongs before the argument, zero if this term is equal to the
argument, and a positive integer if this term belongs after the
argument.
The ordering of terms is first by field, then by text.*/
// public final int compareTo(Term other) {
// if (field == other.field) // fields are interned
// return text.compareTo(other.text);
// else
// return field.compareTo(other.field);
// }
public final int compareTo(Term other) {
if (field == other.field) { // fields are interned
return ckText.compareTo(other.ckText);
} else {
return field.compareToIgnoreCase(other.field);
}
}
/** Resets the field and text of a Term. */
final void set(String fld, String txt) {
field = fld;
text = txt;
ckText = OpacCollator.getInstancePool().getCollationKey(text);
}
public final String toString() { return field + ":" + text; }
private void readObject(java.io.ObjectInputStream in)
throws java.io.IOException, ClassNotFoundException
{
in.defaultReadObject();
field = field.intern();
ckText = OpacCollator.getInstancePool().getCollationKey(text);
}
}
TermBuffer.java:
public final int compareTo(TermBuffer other) {
if (field == other.field) { // fields are interned
return compareChars(text, textLength, other.text, other.textLength);
}
else {
return field.compareTo(other.field);
}
}
private static final int compareChars(char[] v1, int len1,
char[] v2, int len2) {
String v1s = new String(v1,0,len1);
String v2s = new String(v2,0,len2);
OpacCollator oc = OpacCollator.getInstancePool();
CollationKey v1k = oc.getCollationKey(v1s);
CollationKey v2k = oc.getCollationKey(v2s);
return v1k.compareTo(v2k);
}
OpacCollator.java
package org.apache.lucene.index;
import java.text.CollationKey;
import java.text.Collator;
import java.text.ParseException;
import java.text.RuleBasedCollator;
import java.util.BitSet;
import java.util.Locale;
import org.apache.log4j.Logger;
/**
* Collator che considera lo spazio '\u0020' come primo carattere
dell'ordinamento.L'underscore
* sembra essere il primo di tutti
*/
public class OpacCollator extends RuleBasedCollator {
/**
* logger
*/
private static Logger log =
Logger.getLogger(OpacCollator.class.getName());
private static String spacesRules = null;
/** progressivo identificativo oggetto */
// private static int seqIdPool = 0;
/** identificativo dell'oggetto */
private int id = 0;
private final static int POOL =
Integer.parseInt(System.getProperty("sebina.opac.collatorpool", "256"));
private final static OpacCollator[] collatorPool = new
OpacCollator[POOL];
private static BitSet bs = new BitSet(POOL);
// private static int cntPool = 0;
static {
RuleBasedCollator it_ITcollator = (RuleBasedCollator)
Collator.getInstance(new Locale("it", "IT"));
spacesRules = it_ITcollator.getRules().replaceAll("='\t'=", "=");
spacesRules = spacesRules.replaceAll(";'\t' ;", ";");
spacesRules = spacesRules.replaceAll("<'_'", "<'\t'<'\u0020'<'_'");
for (int i = 0; i < POOL; i++) {
try {
collatorPool[i] = new OpacCollator(i);
bs.set(i);
} catch (ParseException e) {
log.fatal("Rules:" + it_ITcollator.getRules(), e);
break;
}
}
}
public static synchronized OpacCollator getInstancePool() {
int pos = -1;
while (pos < 0) {
pos = bs.nextSetBit(0);
}
bs.clear(pos);
return collatorPool[pos];
}
/**
* Constructor for OpacCollator.
*
* @throws ParseException
*/
private OpacCollator() throws ParseException {
super(spacesRules);
this.setStrength(Collator.PRIMARY);
}
/**
* Constructor for OpacCollator.
*
* @param id
* @throws ParseException
*/
public OpacCollator(int ident) throws ParseException {
this();
this.id = ident;
}
/**
* @see java.text.Collator#getCollationKey(String)
*/
public CollationKey getCollationKey(String arg0) {
CollationKey ck = super.getCollationKey(arg0);
bs.set(this.id);
return ck;
}
}
--
Federica FALINI
Divisione Beni Culturali
tel: +39.0544.503.886
fax: +39.0544.461697
e-mail: [email protected]
web: http://www.datamanagement.it
48100 - Ravenna (RA)
Via S.Cavina, n 7
Italy
________________________________
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--
Federica
FALINI
Divisione Beni Culturali
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48100 - Ravenna (RA)
Via S.Cavina, n 7
Italy
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Questo messaggio
di posta elettronica contiene informazioni di carattere confidenziale
rivolte esclusivamente al destinatario sopra indicato. E' vietato
l'uso, la diffusione, distribuzione o riproduzione da parte di ogni
altra persona. Nel caso aveste ricevuto questo messaggio di posta
elettronica per errore, siete pregati di segnalarlo immediatamente al
mittente e distruggere quanto ricevuto (compresi i file allegati) senza
farne copia. This e-mail transmission may contain legally
privileged and/or confidential information. Please do not read it if
you are not the intended recipient(S). Any use, distribution,
reproduction or disclosure by any other person is strictly prohibited.
If you have received this e-mail in error, please notify the sender and
destroy the original transmission and its attachments without reading
or saving it in any manner. |
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